Hi all,
I've already talked about my formulas for generating "tick" surfaces. However, it's possible to extend this formulas to generate much more interesting surfaces.
I'll start with some explanations on how to use it and will show some "extra" use of it
The formulas is described like this :

To apply this formula , you should be able to calculate the derivative form of your original isosurface. If you don't know how to do it, take a look on these pages :
http://en.wikipedia.org/wiki/Derivativehttp://mathworld.wolfram.com/Derivative.html
Once you're familiar with this notation, it's only a matter of minutes to calculate the derivative formula.
The first extension of this formulas can be obtained by generating isosurfaces with more that two successive parts. For example, to have three surfaces , we have only to vary the parameter T and use this formulas :